Square has a brilliantly simple business service producct and Visa (the credit card company) took notice.
Square provides a free credit card reader that works with an iPhone, Android phone or iPad. It can process Visa, MasterCard, American Express and Discover Card credit cards. Square charges a 2.75% fee for each credit card swipe (payment). There is no other fee or contract requirement.
The apparent goal is to convince the 27 million small businesses in the U.S. that do not currently accept credit cards (presumably because of the complexity of doing so using a conventional banking relationship) to use Square to process credit payments.
You can find the free Square iPhone app that works with the free credit card reader at:
Square 1.6 (iTunes App Store)
The free Android app is found here:
Square 1.6.0 (Android Market)